Polymerizable phosphates are obtained, for example, by reacting an unsaturated group-containing alcohol with phosphoric acid anhydride or polyphosphoric acid. JP-A 2003-146992 discloses a method in which a phosphoric acid anhydride suspension solution is added dropwise to an unsaturated group-containing alcohol in the presence of a reducing agent, followed by continuous stirring to thereby produce a polymerizable phosphate improved in hue. Also, WO-A 2002/088151 discloses a method of producing a polymerizable phosphate reduced in the contents of a volatile solvent and polymerizable organic acids produced as byproducts by allowing a polyphosphoric acid and at least one of hydroxyalkyl-α-substituted acrylate to undergo an esterification reaction using a polymerizable phosphate as a reaction solvent.